1. Field of the Invention
The present invention relates to a method of communicating, and more particularly, to a method of performing communicating according to control information in a wireless communication system.
2. Discussion of the Related Art
A General Packet Radio Service (GPRS) is a mobile data service available to users of global system for mobile communication (GSM) and interim standard-136 (IS-136) mobile phones. GPRS is the first high speed digital data service provided by cellular carriers that used the GSM technology.
Second generation (2G) cellular systems combined with GPRS is often described as “2.5G”, that is, a technology between the second (2G) and third (3G) generations of mobile telephony. It provides moderate speed data transfer, by using unused time division multiple access (TDMA) channels in, for example, the GSM system.
GPRS is different from the older circuit-switched data (CSD) connection included in GSM standards. In CSD, a data connection establishes a circuit, and reserves the full bandwidth of that circuit during the lifetime of the connection. GPRS is packet-switched which means that multiple users share the same transmission channel, only transmitting when they have data to send. This means that the total available bandwidth can be immediately dedicated to those users who are actually sending at any given moment, providing higher utilization where users only send or receive data intermittently. Web browsing, receiving e-mails as they arrive and instant messaging are examples of uses that require intermittent data transfers, which benefit from sharing the available bandwidth.
With mobility of mobile devices using the GPRS system, it is important that services are provided effectively and efficiently between the network and the mobile device.